Early Identification of Clinically Isolated Syndrome - How this is Best Achieved and the Implications for Patient Outcomes

Magnetic resonance imaging (MRI) evidence for dissemination in space (DIS) and dissemination in time (DIT) is used within the McDonald criteria for the diagnosis of multiple sclerosis (MS). These criteria are complex and in some patients several MRI examinations are needed to achieve an accurate diagnosis. In order to make an earlier diagnosis of clinically definite multiple sclerosis (CDMS) in patients with clinically isolated syndromes (CIS), new criteria have been proposed in which DIS and DIT requirements are simpler, maximising sensitivity and conserving specificity. These new data have led to a new proposal of MRI criteria for MS diagnosis. The historical evolution of MS criteria and the new evidence are reviewed in this article.